Reliability of Using a Handheld Tablet and Application to Measure Lower
Extremity Alignment Angles
Extremity Alignment Angles
King D.L, Belyea B.C. J Sport Rehabil; 2014; ahead
of print
of print
Take Home
Message: A tablet application is a promising, reliable tool to capture
objective landing kinematics. Intra-rater reliability is good to excellent with
an average of 6 trials. Inter-rater reliability is fair to excellent depending
on the level of experience.
Message: A tablet application is a promising, reliable tool to capture
objective landing kinematics. Intra-rater reliability is good to excellent with
an average of 6 trials. Inter-rater reliability is fair to excellent depending
on the level of experience.
Evaluating
an athlete’s risk for injury is necessary to tailor injury prevention plans for
an athlete. To assess risk for injury, medical personnel most commonly employ visual
observations of an exercise (e.g., drop vertical jump); however, errors in
visual estimations of lower extremity joint angles have been reported.
Utilizing a tablet with a movement analysis application is a more objective way
of determine joint angles during functional movement. Though, the reliability
of this new tool has not been established. Therefore, the authors measured the inter–rater and inter-trial
reliability among multiple researchers who evaluated 23 healthy college
students using an iPad2 and the KinesioCapture application.
The athletes performed 6 two-footed drop vertical jumps, while 1 researcher with
experience with 2-D videography captured all the trials. Then, 4 researchers (2
experienced & 2 novices) analyzed the previously captured video for the
degrees of knee and hip flexion. The researchers measured 3 of the jumps in the
sagittal plane followed by 3 jumps in the frontal plane. Inter-rater
reliability ranged from low (0.39) to excellent (0.98). Experienced raters
performed slightly better with moderate to good reliability (0.69-0.93)
compared with the novice raters (0.39-0.98). Novice and experienced raters were
more consistent at measuring joint angles at maximum knee flexion than at
initial ground contact. Averaging the trials offered better reliability than
assessing each trial separately.
an athlete’s risk for injury is necessary to tailor injury prevention plans for
an athlete. To assess risk for injury, medical personnel most commonly employ visual
observations of an exercise (e.g., drop vertical jump); however, errors in
visual estimations of lower extremity joint angles have been reported.
Utilizing a tablet with a movement analysis application is a more objective way
of determine joint angles during functional movement. Though, the reliability
of this new tool has not been established. Therefore, the authors measured the inter–rater and inter-trial
reliability among multiple researchers who evaluated 23 healthy college
students using an iPad2 and the KinesioCapture application.
The athletes performed 6 two-footed drop vertical jumps, while 1 researcher with
experience with 2-D videography captured all the trials. Then, 4 researchers (2
experienced & 2 novices) analyzed the previously captured video for the
degrees of knee and hip flexion. The researchers measured 3 of the jumps in the
sagittal plane followed by 3 jumps in the frontal plane. Inter-rater
reliability ranged from low (0.39) to excellent (0.98). Experienced raters
performed slightly better with moderate to good reliability (0.69-0.93)
compared with the novice raters (0.39-0.98). Novice and experienced raters were
more consistent at measuring joint angles at maximum knee flexion than at
initial ground contact. Averaging the trials offered better reliability than
assessing each trial separately.
This
is an important study since properly operating new and affordable tools are
imperative for better objective measures to determine an athlete’s risk of
injury. The authors demonstrated that the handheld tablet is a reliable tool to
measure knee and hip flexion during a drop vertical jump. The authors also
found that experience as well as multiple trials are necessary for optimal reliability.
An average of multiple trials may represent the true movement pattern, and
reduces the influence of errors (e.g., a bad movement on one trial, error in
one measurement). Future research needs to determine how much training medical
personnel requires before becoming an experienced rater. Furthermore, all of
the videos were captured by a trained individual so we may need to train
clinicians to capture an optimal video for these analyses. Future research,
will have to determine how much measurement error could be caused by changes in
how the videos are acquired. Additionally, assessing how many trials are
required for a reliable reading is necessary to apply this tool for functional
use. It will also be interesting to see how these measurements compare to
traditional motion analysis systems. While more research is needed this study shows
that measuring lower extremity movement can be reliably assessed on a tablet if
one experienced person records the video, average joint angles are calculated
across three trials, and the person doing the measurement is adequately
trained. This study is a good reminder that clinicians should check their
reliability over time and among other clinicians in a clinic to ensure
consistency.
is an important study since properly operating new and affordable tools are
imperative for better objective measures to determine an athlete’s risk of
injury. The authors demonstrated that the handheld tablet is a reliable tool to
measure knee and hip flexion during a drop vertical jump. The authors also
found that experience as well as multiple trials are necessary for optimal reliability.
An average of multiple trials may represent the true movement pattern, and
reduces the influence of errors (e.g., a bad movement on one trial, error in
one measurement). Future research needs to determine how much training medical
personnel requires before becoming an experienced rater. Furthermore, all of
the videos were captured by a trained individual so we may need to train
clinicians to capture an optimal video for these analyses. Future research,
will have to determine how much measurement error could be caused by changes in
how the videos are acquired. Additionally, assessing how many trials are
required for a reliable reading is necessary to apply this tool for functional
use. It will also be interesting to see how these measurements compare to
traditional motion analysis systems. While more research is needed this study shows
that measuring lower extremity movement can be reliably assessed on a tablet if
one experienced person records the video, average joint angles are calculated
across three trials, and the person doing the measurement is adequately
trained. This study is a good reminder that clinicians should check their
reliability over time and among other clinicians in a clinic to ensure
consistency.
Questions for
Discussion: Do you have access to a tablet? If so, would you use the tablet to
measure landing kinematics? Do you measure/observe landing kinematics to
identify athletes at risk for knee injuries?
Discussion: Do you have access to a tablet? If so, would you use the tablet to
measure landing kinematics? Do you measure/observe landing kinematics to
identify athletes at risk for knee injuries?
Written
by: Jane McDevitt, PhD
by: Jane McDevitt, PhD
Reviewed
by: Jeffrey Driban
by: Jeffrey Driban
Related
Posts:
Posts:
King DL, & Belyea BC (2014). Reliability of Using a Handheld Tablet and Application to Measure Lower Extremity Alignment Angles. Journal of Sort Rehabilitation PMID: 25310432
Yes, I have access to a tablet although it is not an iPad. As someone who is interested in research, I think that I would definitely like to try using the tablet to do some 2D motion capture. I would also like to see the inter-rater reliability for values in the frontal plane, but realize that there are probably limitations with the traditional landmark placements.
I feel that the use of 2D videography for measuring joint angles will become more common with athletic trainers. It is a useful tool for us that is both functional and cheap. Using 3D motion capture is great, but it takes time, clinician experience, and the systems are costly. 2D motion analysis is a great tool for athletic trainers who are not fortunate enough to have access to 3D analysis.
I would definitely use this in the clinic to measure landing kinematics if I knew specifically what degrees and angles were putting athletes at risk. Since landing in varus is rare, I would need to know what to look for when I find a valgus collapse. I think an interesting part that may be missing from this is comparison to 3D kinematics and the reliability between the two.
I think that utilizing technology in this way will provide clinicians with valuable tools and information that can improve the way we identify injury risk and movement patterns. I agree that it would require training for the clinicians but by increasing the number of trained professionals, it could increase the prevalence of use throughout the healthcare professions. I also think that 2D imaging and motion analysis is tricky and standardized procedures must be provided in order to determine the distance, height, angles, and frame rate of the cameras if being used for measure joint kinematics. I think if we were able to standardized these variables and train the necessary readers then this tool would prove to be very effective. In the smart phone and technological age we are in now, this would also stimulate a lot of interest among the younger healthcare professionals.
Great points, I agree I think athletic trainers will be using this type of technology more and more as it becomes more readily available. I believe Kyle brings up a great point, that these protocols will need to be specific for each athlete (sex, height, weight, q-angle, so many variables to consider), so I think there is still more room to grow before this type of technology will be consistently used in the athletic training room.